Differences between version 4 and previous revision of HereStrings.
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| Newer page: | version 4 | Last edited on Saturday, December 9, 2006 11:20:40 pm | by BenStaz | Revert |
| Older page: | version 1 | Last edited on Saturday, December 9, 2006 11:08:15 pm | by BenStaz | Revert |
@@ -2,23 +2,16 @@
A variant of here documents, the format is:
*command <<< "string"
-The
string is supplied
to the
command on its standard input. Remember of course
, that "string"
can be replaced with a variable
.
+A here
string uses a form of I/O redirection
to feed a command to an *interactive* program or a
command, such as ftp, cat, ex or read. This
can be extremely handy
.
I find Here String's very useful to easily assign values to multiple variables.
-The 'read' command claims to read from the standard input, but it doesn't actually seem to happen when a pipe is involved. Each command in the pipeline gets executed in its own subshell and so the variables are set there and not passed back to the parent process. This is why
-
-*echo "red blue red" | read a b c
-
-DOES NOT WORK
-
-
-How to get around this problem using Here Strings
:
+For Example
:
*IFS=: ; read foo bar moo <<< "yellow:red:blue";
Now try:
*echo $foo $bar $moo
and hopefully the value of the three variables will be displayed for you.
